This study presents a comprehensive nonlinear dynamic analysis of curved sandwich beams subjected to high-velocity moving point loads, focusing on their buckling behavior. The sandwich structure comprises carbon nanotube (CNT)-reinforced nanocomposite face sheets and a closed-cell foam core. The effective properties of the nanocomposite faces are determined using the modified rule of mixtures, while the mechanical behavior of the foam core accounts for cell-wall bending, face stretching, and the internal gas pressure, providing a realistic representation of its nonlinear response. The third-order shear deformation theory (TSDT) is adopted to capture transverse shear effects, rotary inertia, and to satisfy the traction-free boundary conditions on the outer surfaces of the beam. Geometric nonlinearity is incorporated through the von Kármán strain-displacement relations. The total potential energy of the system is formulated and discretized using a nonlinear Ritz-based approach, leading to a set of governing equations of motion. These equations are integrated in the time domain using the Hilber–Hughes–Taylor (HHT) method, which enhances numerical stability and introduces controllable numerical dissipation for high-frequency response components, which makes it well-suited for nonlinear transient dynamics. The resulting nonlinear algebraic systems at each time step are solved iteratively using the Newton–Raphson method, ensuring convergence under strong geometric nonlinearities. Furthermore, the Budiansky instability criterion is employed to determine the critical load magnitude and velocity thresholds for dynamic buckling initiation. The proposed formulation effectively captures the complex interaction between geometric nonlinearity, advanced material behavior, and dynamic loading, offering valuable insights into the instability mechanisms of curved sandwich nanocomposite structures under transient localized excitations.
Zhao et al. (Wed,) studied this question.